1. Field of the Invention
The present invention relates to an image processing apparatus suitable particularly for color printing, wherein an inputted multi-value image data is binarized to output an image such as characters, graphics, and the like.
2. Related Background Art
In a conventional printing apparatus wherein an inputted multi-value image data is binarized to output a color image such as characters, graphics, and the like, a pattern necessary for a binarization process is generated in accordance with color designating information which designates the color of a character or the like. Specifically, a host computer generates a multi-value data representative of gradations of R (red), G (green), and B (blue), or Y (yellow), M (magenta), C (cyan), and K (black), in response to color designating commands. Upon reception of the multi-value data from the host computer, the printing apparatus generates binarization patterns of Y, M, C, and K having the designated gradations, and prints out characters or the like with designated colors.
The following disadvantages are, however, associated with the above-described related art.
(1) A large amount of color designating information is required. For example, if a complicated color image is to be printed, it becomes necessary to designate a number of colors using a corresponding number of color designating commands, and to generate patterns as many as the number of color designating commands, taking a long time for printing the image.
(2) Since the type of patterns to be generated are limited, it is not possible to generate optimum binarization patterns.